diff --git a/Dockerfile b/Dockerfile
index f1ff40e..544f072 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -7,7 +7,7 @@ ENV HOME="/root"
 ENV TERM="xterm"
 
 # set version for s6 overlay
-ARG OVERLAY_VERSION="v1.18.1.3"
+ARG OVERLAY_VERSION="v1.18.1.5"
 ARG OVERLAY_ARCH="amd64"
 ARG OVERLAY_URL="https://github.com/just-containers/s6-overlay/releases/download"
 ARG OVERLAY_WWW="${OVERLAY_URL}"/"${OVERLAY_VERSION}"/s6-overlay-"${OVERLAY_ARCH}".tar.gz
@@ -21,11 +21,16 @@ RUN \
 	/config \
 	/defaults
 
-# install packages
+# copy sources
+COPY sources.list /etc/apt/
+
+# install apt-utils
 RUN \
  apt-get update && \
  apt-get install -y \
 	apt-utils && \
+
+# install packages
  apt-get install -y \
 	curl && \
 
diff --git a/sources.list b/sources.list
new file mode 100644
index 0000000..0eaeeec
--- /dev/null
+++ b/sources.list
@@ -0,0 +1,33 @@
+# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
+# newer versions of the distribution.
+
+deb http://archive.ubuntu.com/ubuntu/ xenial main restricted
+deb-src http://archive.ubuntu.com/ubuntu/ xenial main restricted
+
+## Major bug fix updates produced after the final release of the
+## distribution.
+deb http://archive.ubuntu.com/ubuntu/ xenial-updates main restricted
+deb-src http://archive.ubuntu.com/ubuntu/ xenial-updates main restricted
+
+## Uncomment the following two lines to add software from the 'universe'
+## repository.
+## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
+## team. Also, please note that software in universe WILL NOT receive any
+## review or updates from the Ubuntu security team.
+deb http://archive.ubuntu.com/ubuntu/ xenial universe multiverse
+deb-src http://archive.ubuntu.com/ubuntu/ xenial universe multiverse
+deb http://archive.ubuntu.com/ubuntu/ xenial-updates universe multiverse
+deb-src http://archive.ubuntu.com/ubuntu/ xenial-updates universe multiverse
+
+## N.B. software from this repository may not have been tested as
+## extensively as that contained in the main release, although it includes
+## newer versions of some applications which may provide useful features.
+## Also, please note that software in backports WILL NOT receive any review
+## or updates from the Ubuntu security team.
+# deb http://archive.ubuntu.com/ubuntu/ xenial-backports main restricted
+# deb-src http://archive.ubuntu.com/ubuntu/ xenial-backports main restricted
+
+deb http://archive.ubuntu.com/ubuntu/ xenial-security main restricted
+deb-src http://archive.ubuntu.com/ubuntu/ xenial-security main restricted
+deb http://archive.ubuntu.com/ubuntu/ xenial-security universe multiverse
+deb-src http://archive.ubuntu.com/ubuntu/ xenial-security universe multiverse